ai-agents-bedrock-claude3-mess-using-langchain-s-bedrock-llm-with-a-claude-3-mode-cd66a346

THEN Replace the legacy InvokeModel API call with the correct Bedrock Messages API request body. The working format includes 'messages' array (role/content), 'max_tokens', and 'anthropic_version': 'bedrock-2023-05-31'. Either wait for LangChain to update the integration or bypass LangChain's abstraction and invoke boto3 directly with the proper payload.

import boto3
bedrock = boto3.client('bedrock-runtime', 'us-east-1')
body = {
    "max_tokens": 1024,
    "system": "Today is January 1, 2024.",
    "messages": [{"role": "user", "content": "Hello, Claude"}],
    "anthropic_version": "bedrock-2023-05-31"
}
response = bedrock.invoke_model(modelId='anthropic.claude-3-sonnet-20240229-v1:0', body=json.dumps(body))